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How does increasing temperature change the rate and outcome of some chemical reactions?

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combustion — chemical reaction Log burning in a fire. Burning wood is an example of a chemical reaction in which wood in the presence of heat and oxygen is transformed into carbon dioxide, water vapor, and ash.

Increasing the temperature of a chemical reaction significantly accelerates its rate. According to the collision theory, a reaction occurs when molecules collide with sufficient kinetic energy to exceed the activation energy required to reach the transition state. As temperature rises, molecules move more rapidly, increasing both the frequency of collisions and the proportion of molecules possessing the energy necessary to overcome the activation barrier.12

The Arrhenius equation mathematically describes this relationship, predicting that even a small increase in temperature leads to a marked rise in the reaction-rate constant. In practical terms, chemists often increase temperature to make slow reactions occur within a reasonable timeframe.23

Regarding the outcome, temperature influences chemical equilibrium. For example, in exchange reactions, high temperatures tend to promote a random distribution of isotopes, whereas lower temperatures can favor specific isotopic configurations based on bond strength. Thus, temperature control is essential for managing both the speed and the final product distribution of chemical processes.41